CN103368425B - A kind of synchronous rectification driving circuit - Google Patents
A kind of synchronous rectification driving circuit Download PDFInfo
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Abstract
This application discloses a kind of synchronous rectification driving circuit, comprise: obtain and export the sampled voltage of the input voltage size characterizing described circuit of synchronous rectification sample circuit, control rectifying tube and continued flow tube alternate conduction driving main circuit, when rectifying tube conducting, the clamp circuit of the grid voltage of switching tube described in clamper and when described continued flow tube conducting, the grid of described rectifying tube is discharged, to turn off the discharge circuit of described rectifying tube fast; Described driving main circuit comprises the first resistance and switching tube; The application is by the electric discharge of the dividing potential drop of switching tube, the clamper of clamp circuit and discharge circuit, achieve the control to rectifying tube driving voltage, avoid the forward high pressure of rectifying tube grid source electrode and the formation of negative sense high pressure under wide-voltage range initial conditions, eliminate the hidden danger that the rectifying tube grid source that causes because input voltage is too high punctures; In addition, the embodiment of the present application structure is simple, and cost is low, reliability is high.Therefore, the embodiment of the present application solves the problem of prior art.
Description
Technical Field
The application relates to the technical field of power supply electronics, in particular to a synchronous rectification drive circuit.
Background
In the field of electronic technology, the application of synchronous rectification technology is becoming more and more widespread. The key of the synchronous rectification technology is the driving technology, and common driving modes comprise self-driving, winding direct driving and other driving. The self-driving and winding direct driving modes are difficult to consider positive and negative driving voltages under the condition of wide voltage range input, and both the positive and negative driving voltages can be too high, so that the rectifier tube is broken down, and the self-driving and winding direct driving mode can only be applied to the condition of narrow input voltage range; the driving mode of the driving circuit has the advantages of complex circuit structure, high cost and poor reliability.
Therefore, a synchronous rectification driving circuit with simple structure and low cost, which can be applied in any input voltage range, is needed.
Disclosure of Invention
In view of the above, an object of the present invention is to provide a synchronous rectification driving circuit, so as to solve the problems of narrow input voltage range in the conventional self-driving and winding direct driving manner, and complicated circuit structure, high cost and poor reliability in the driving manner.
In order to achieve the above purpose, the present application provides the following technical solutions:
a synchronous rectification drive circuit is applied to a synchronous rectification circuit; the synchronous rectification circuit comprises a rectification tube and a follow current tube; the synchronous rectification drive circuit comprises:
the sampling circuit is used for acquiring and outputting sampling voltage representing the input voltage of the synchronous rectification circuit;
the driving main circuit comprises a first resistor and a switching tube and is used for controlling the rectifying tube and the follow current tube to be conducted alternately;
the clamping circuit is used for clamping the grid voltage of the switching tube when the rectifying tube is conducted;
the discharge circuit is used for discharging the grid electrode of the rectifying tube when the follow current tube is conducted so as to rapidly turn off the rectifying tube; wherein,
a first output end of the sampling circuit is respectively connected with one end of the first resistor and an input end of the clamping circuit; the second output end of the sampling circuit is connected with the negative output end of the synchronous rectification circuit;
the other end of the first resistor is connected with the drain electrode of the switch tube, and the source electrode of the switch tube is connected with the grid electrode of the rectifier tube; the grid electrode of the switching tube is connected to the output end of the clamping circuit;
the discharge circuit is respectively connected with the grid of the rectifier tube and the drain of the follow current tube.
Preferably, the discharge circuit includes a first diode; the anode of the first diode is connected with the grid electrode of the rectifier tube, and the cathode of the first diode is connected with the drain electrode of the follow current tube.
Preferably, the clamping circuit comprises a third diode, a voltage stabilizing diode, a second resistor, a third resistor and a capacitor;
the anode of the third diode is used as the input end of the clamping circuit; the cathode of the third diode is connected to one end of the second resistor;
the cathode of the voltage stabilizing diode is used as the output end of the clamping circuit and is connected to the other end of the second resistor in parallel; the anode of the voltage stabilizing diode is connected with the negative output end of the synchronous rectification circuit;
and the third resistor and the capacitor are respectively connected with the voltage stabilizing diode in parallel.
Preferably, the synchronous rectification circuit further comprises a transformer having a primary winding and a secondary winding;
the sampling circuit is specifically the secondary winding; and the homonymous end of the secondary winding is used as a first output end of the sampling circuit, and the heteronymous end of the secondary winding is used as a second output end of the sampling circuit.
Preferably, the synchronous rectification circuit further comprises a transformer having a primary winding and a secondary winding;
the sampling circuit is specifically a first auxiliary winding coupled with the primary winding; the homonymous end of the first auxiliary winding is used as a first output end of the sampling circuit, and the synonym end of the first auxiliary winding is used as a second output end of the sampling circuit.
Preferably, the main driving circuit further includes a second diode connected in series between the first output terminal of the sampling circuit and the first resistor, an anode of the second diode is connected to the first output terminal of the sampling circuit, and a cathode of the second diode is connected to the first resistor.
Preferably, the synchronous rectification circuit further comprises an output inductor and a transformer having a primary winding and a secondary winding; the homonymous end of the output inductor is connected with the homonymous end of the secondary winding, and the heteronymous end of the output inductor is used as the positive output end of the synchronous rectification circuit;
the sampling circuit is specifically a second auxiliary winding coupled with the output inductor; and the homonymous end of the second auxiliary winding is used as a first output end of the sampling circuit, and the synonym end of the second auxiliary winding is used as a second output end of the sampling circuit.
Preferably, the main driving circuit further includes a second diode connected in series between the first output terminal of the sampling circuit and the first resistor, an anode of the second diode is connected to the first output terminal of the sampling circuit, and a cathode of the second diode is connected to the first resistor.
Preferably, the topological structure of the synchronous rectification circuit is a forward primary side active clamp circuit topology, a forward secondary side active clamp circuit topology or a capacitor reset forward circuit topology.
According to the technical scheme, the control of the driving voltage of the rectifier tube Q2 is realized through the voltage division of the switch tube Q5, the clamping of the clamping circuit and the discharging of the discharging circuit, the positive high voltage and the negative high voltage of the grid source electrode of the rectifier tube Q2 under the condition of wide voltage range input are avoided, and the input voltage V is eliminatedinThe potential hazard of gate-source breakdown of the rectifier tube Q2 caused by overhigh voltage; in addition, the embodiment of the application has the advantages of simple structure, low cost and high reliability. Accordingly, the embodiments of the present application solve the problems of the prior art.
Drawings
In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.
Fig. 1 is a structural diagram of a synchronous rectification driving circuit according to an embodiment of the present application;
fig. 2 is a structural diagram of a synchronous rectification driving circuit according to a second embodiment of the present application;
fig. 3 (a) is a structural diagram of a synchronous rectification driving circuit using a secondary winding as a sampling circuit according to an embodiment of the present application;
fig. 3 (b) is a structural diagram of a synchronous rectification driving circuit using a first auxiliary winding as a sampling circuit according to an embodiment of the present application;
fig. 3 (c) is a structural diagram of a synchronous rectification driving circuit using a second auxiliary winding as a sampling circuit according to an embodiment of the present application;
fig. 4 is a schematic diagram of a synchronous rectification driving circuit applied to a forward primary side active clamp topology secondary side synchronous rectification circuit provided in the embodiment of the present application;
fig. 5 is a schematic diagram of a synchronous rectification driving circuit applied to a capacitor reset forward topology secondary synchronous rectification circuit according to an embodiment of the present application.
Detailed Description
The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.
The embodiment of the application discloses a synchronous rectification drive circuit, which aims to solve the problems that the input voltage range of the existing self-driving and winding direct driving mode is narrow, and the circuit structure of the existing self-driving and winding direct driving mode is complex, high in cost and poor in reliability.
The embodiment of the application provides a synchronous rectification driving circuit, which is applied to a synchronous rectification circuit. Generally, the synchronous rectification circuit 100 includes a transformer T1, a rectifier Q2 and a follow current Q3, as shown in fig. 1. The synchronous rectification driving circuit provided by the embodiment comprises a sampling circuit 110, a driving main circuit 120, a clamping circuit 130 and a discharging circuit 140. The main driving circuit 120 includes a first resistor R1 and a switching tube Q5.
A first output end of the sampling circuit 110 is respectively connected with one end of the first resistor R1 and an input end of the clamping circuit 130; a second output end of the sampling circuit 110 is connected to a negative output end of the synchronous rectification circuit 100; the other end of the first resistor R1 is connected with the drain of the switch tube Q5, and the source of the switch tube Q5 is connected with the grid of the rectifier tube Q2; the grid electrode of the switching tube Q5 is connected with the output end of the clamping circuit 130; the discharge circuit 140 is connected to the gate of the rectifier Q2 and the drain of the follow current Q3, respectively.
The sampling circuit 110 is used for obtaining and outputting an input voltage V representing the synchronous rectification circuit 100inA magnitude of the sampled voltage; the main driving circuit 120 is used for controlling the rectifier tube Q2 and the follow current tube Q3 to be alternately conducted; the clamping circuit 130 is used for clamping the gate voltage of the switching tube Q5 to a preset value when the rectifying tube Q2 is turned on; the discharge circuit 140 is used for discharging the gate of the rectifier Q2 when the freewheeling Q3 is turned on.
The synchronous rectification drive circuit controls the operating state (rectification/freewheeling) of the synchronous rectification circuit by turning on/off the drive rectifier Q2 and the freewheeling tube Q3, that is: when the dotted terminal of the transformer T1 of the synchronous rectification circuit 100 is positive, the rectifier Q2 is first turned on through a body diode, so that the gate-source voltage of the freewheeling tube Q3 is clamped to zero potential, and the freewheeling tube Q3 is turned off; meanwhile, the main driving circuit 120 charges a gate-source junction capacitor of the rectifier tube Q2, so that the rectifier tube Q2 is turned on, and the synchronous rectifier circuit 100 is in a rectification stage; when the dotted terminal of the transformer T1 is negative, the freewheeling tube Q3 is turned on, the dotted terminal voltage of the secondary winding T1A of the transformer T1 is clamped to zero potential, the gate charge of the rectifier tube Q2 is rapidly discharged through the discharge circuit 140, the gate-source voltage of the rectifier tube Q2 is clamped to zero potential by the diode D1, reliable turn-off of the rectifier tube Q2 is realized, and the synchronous rectification circuit 100 is in the freewheeling stage.
In the conventional self-driving method and the winding direct driving method, the rectifier Q2 is directly driven by the output voltage of the secondary winding T1A. When the primary input voltage of the transformer T1 is high, the output voltage of the secondary winding T1A is also high, and the gate-source of the rectifier Q2 will have a positive high voltage (when the dotted terminal of the transformer T1 is positive) or a negative high voltage (when the dotted terminal of the transformer T1 is negative), which may cause the gate-source breakdown of the rectifier Q2, so the reliability is low.
The synchronous rectification driving circuit provided by the embodiment of the application can avoid the overhigh driving voltage of the rectifier tube Q2 and eliminate the hidden danger of gate-source breakdown, and the principle is as follows:
when the end of the transformer T1 of the synchronous rectification circuit 100 with the same name is positive, that is, the synchronous rectification circuit 100 is in the rectification stage, the voltage collected by the sampling circuit 110 is not directly applied between the gate and the source of the rectifier Q2 due to the existence of the switch Q5, but is shared by the drain and the source of the switch Q5 and the gate and the source of the rectifier Q2, and the input voltage V is shared by the drain and the source of the switch Q5inThe higher the voltage collected by the sampling circuit 110, the higher the drain-source voltage V of the switching tube Q5Q5_dsAnd gate-source voltage V of rectifier Q2Q2_gsThe higher is also; at the same time, the clamping circuit 130 clamps the gate voltage V of the switching tube Q5Q5_gClamped to the preset value, the grid voltage V of the rectifier tube Q2Q2_gEqual to the source voltage V of the switching tube Q5Q5_sI.e. VQ2_g=VQ5_s=VQ5_g-VQ5_gs(ii) a Wherein, VQ5_gsIs the gate-source voltage of the switching tube Q5. When V isQ2_gDependent on the input voltage VinWhen rising, due to VQ5_gIs maintained at the above-mentioned preset value, so VQ5_gsDecreases accordingly when the input voltage VinToo high a temperature of the molten steel is required,result in VQ5_gsLess than threshold voltage V of switching tube Q5thWhen the switch tube Q5 is turned off, the high forward voltage of the gate-source of the rectifier tube Q2 is avoided.
When the dotted terminal of the transformer T1 is negative, i.e. the synchronous rectification circuit 100 is in the freewheeling stage, the gate of the rectifier Q2 is rapidly discharged through the discharge circuit 140, and the gate voltage V of the rectifier Q2Q2_gClamped to zero potential, the rectifier tube Q2 is turned off quickly and reliably, and negative voltage between the gate and the source of the rectifier tube Q2 is avoided.
According to the structure and the working principle, the voltage division of the switch tube, the clamping of the clamping circuit and the discharging of the discharging circuit are adopted, the positive high voltage and the negative high voltage of the gate source electrode of the rectifier tube Q2 under the condition of wide voltage range input are avoided, and the input voltage V is eliminatedinThe potential hazard of gate-source breakdown of the rectifier tube Q2 caused by overhigh voltage; in addition, the embodiment of the application has the advantages of simple structure, low cost and high reliability. Accordingly, the embodiments of the present application solve the problems of the prior art.
Further, in the above embodiments, the preset voltage level of the clamp circuit 130 can be changed or different threshold voltages V can be selectedthThe switching tube Q5 of (1) sets the upper limit value of the driving voltage of the rectifying tube Q2 to adapt to different input voltage ranges.
The second embodiment of the present application provides another synchronous rectification driving circuit applied to a synchronous rectification circuit. Referring to fig. 2, the synchronous rectification circuit 200 includes a rectifier Q2 and a follow current Q3. The synchronous rectification drive circuit comprises a sampling circuit 210, a drive main circuit 220, a clamping circuit 230 and a discharging circuit 240.
The main driving circuit 220 comprises a first resistor R1 and a switching tube Q5; the clamp circuit 230 comprises a third diode D3, a zener diode D4, a second resistor R2, a third resistor R3 and a capacitor C; the discharge circuit 240 includes a first diode D1.
The connection relationship among the above components is: a first output end of the sampling circuit 210 is respectively connected with one end of a first resistor R1 and an anode of a third diode D3 (i.e., the input end of the clamping circuit 230); a second output end of the sampling circuit 210 is connected to the negative output end of the synchronous rectification circuit 100; the other end of the first resistor R1 is connected to the drain of the switch tube Q5. The cathode of the third diode D3 is connected to one end of the second resistor R2; the other end of the second resistor R2 is connected to the cathode of the zener diode D4, and the cathode of the zener diode D4 is connected to the gate of the switching tube Q5 as the output end of the clamping circuit 230; the anode of the voltage-stabilizing diode D4 is connected to the negative output end of the synchronous rectification circuit 200; the third resistor R3 and the capacitor C are respectively connected in parallel with the voltage stabilizing diode D4. The source of the switching tube Q5 is connected with the grid of the rectifier tube Q2; the anode of the first diode D1 is connected to the gate of the rectifier Q2, and the cathode of the first diode D1 is connected to the drain of the follow current Q3.
The sampling circuit 210 is used for obtaining and outputting an input voltage V representing a synchronous rectification circuitinA magnitude of the sampled voltage; the main driving circuit 220 is used for controlling the rectifier tube Q2 and the follow current tube Q3 to be alternately conducted; when the end of the transformer T1 of the synchronous rectification circuit 200 with the same name is positive, that is, the synchronous rectification circuit 200 is in the rectification stage, the first diode D1 is turned off in the reverse direction, the third diode D3 is turned on, and the capacitor C is charged to the regulated voltage value of the voltage regulator diode D4 through the second resistor R2, so as to clamp the gate voltage of the switching tube Q5 to the regulated voltage value (that is, the clamp voltage preset value of the clamp circuit 230); when the dotted terminal of the transformer T1 is negative, that is, the synchronous rectification circuit 200 is in the freewheeling stage, the dotted terminal voltage of the transformer T1 secondary winding T1A is clamped to zero by the freewheeling tube Q3, the first diode D1 is positively turned on, discharges the gate of the rectification tube Q2, and finally clamps the gate-source voltage of the rectification tube Q2 to zero, thereby achieving the fast and reliable turn-off of the rectification tube Q2, and preventing the negative voltage from appearing between the gate and the source of the rectification tube Q2.
The second embodiment provides a specific structure of the clamp circuit and the discharge circuit, and realizes that: when the rectifier Q2 is turned on, the gate voltage of the switching tube Q5 is clamped by the clamping circuit 230; when the freewheeling tube Q3 is turned on, the gate of the freewheeling tube Q2 is discharged by the discharge circuit 240. Thereby avoiding the wholeThe positive high voltage and the negative high voltage of the grid source electrode of the flow tube Q2 are formed, and the input voltage V is eliminatedinThe potential hazard of gate-source breakdown of the rectifier tube Q2 caused by overhigh voltage; in addition, the embodiment of the application has the advantages of simple structure, low cost and high reliability. Accordingly, the embodiments of the present application solve the problems of the prior art.
Referring to fig. 3 (a), 3 (b) and 3 (c), the embodiment of the present application provides three specific structures of a sampling circuit. It should be noted that there are various sampling modes of the sampling circuit for the input voltage Vin of the synchronous rectification circuit, and the structures of the corresponding sampling circuits are different from each other, and the present application is not limited to the above three structures.
As shown in fig. 3 (a), the sampling circuit 310a directly uses the secondary winding T1A of the transformer T1 in the synchronous rectification circuit 300, which greatly simplifies the circuit structure. Specifically, the dotted terminal of the secondary winding T1A is used as the first output terminal of the sampling circuit 310a, and is connected to the driving main circuit 320a and the clamping circuit 330, respectively; the synonym terminal of the secondary winding T1A is used as the second output terminal of the sampling circuit 310a and is connected to the negative output terminal of the synchronous rectification circuit 300.
As shown in fig. 3 (b), the sampling circuit 310b employs a first auxiliary winding T1B coupled to the primary winding of a transformer T1; the dotted terminal of the first auxiliary winding T1B is used as the first output terminal of the sampling circuit 310b, and is connected to the driving main circuit 320b and the clamping circuit 330 respectively; the synonym terminal of the first auxiliary winding T1B is used as the second output terminal of the sampling circuit 310b, and is connected to the negative output terminal of the synchronous rectification circuit 300.
As shown in fig. 3 (c), the sampling circuit 310c employs a second auxiliary winding L1A coupled to the output inductor L1 of the synchronous rectification circuit 300; the homonymous end of the output inductor L1 is connected with the homonymous end of the secondary winding T1A, and the heteronymous end of the output inductor L1 is used as the positive output end of the synchronous rectification circuit 300 c; the dotted terminal of the second auxiliary winding L1A is used as the first output terminal of the sampling circuit 310c, and is connected to the driving main circuit 320c and the clamping circuit 330 respectively; the second auxiliary winding L1A has its alias terminal connected to the negative output terminal of the synchronous rectification circuit 300 as the second output terminal of the sampling circuit 310 c.
When the sampling circuit adopts the first auxiliary winding T1B or the second auxiliary winding L1A, the main driving circuit further includes a second diode D2 in addition to the first resistor R1 and the switching tube Q5, for preventing reverse voltage from being formed between the drain and source electrodes of the switching tube Q5 and between the gate and source electrodes of the rectifying tube when the end of the transformer T1 with the same name is negative.
As shown in the driving main circuit 320b in fig. 3 (b) and the driving main circuit 320c in fig. 3 (c), the second diode D2 is connected in series between the first output terminal of the sampling circuit and the first resistor R1: the anode of the second diode D2 is connected to the first output terminal of the sampling circuit, and the cathode is connected to the first resistor R1. When the dotted terminal of the transformer T1 is positive, the second diode D2 is conducted in the forward direction to drive the main circuit to work normally; when the dotted terminal of the transformer T1 is negative, the second diode D2 is turned off in the reverse direction, and no reverse voltage is generated between the drain and source of the switching transistor Q5 and between the gate and source of the rectifying transistor.
In addition, if the sampling circuit directly adopts the secondary winding T1A of the transformer, when the end of the transformer T1 with the same name is negative, the potential of the end with the same name of the secondary winding T1A is clamped to zero by the current-continuing tube Q3 which is conducted, so that an anti-reverse element does not need to be added in the driving main circuit 320 a.
The three structures of the sampling circuit have the advantages that: in the sampling circuit 320a shown in fig. 3 (a), since the secondary winding of the transformer is directly used and no anti-reverse component is required to be added in the driving main circuit 320a, the circuit structure is greatly simplified and the reliability of the circuit is improved; the sampling circuit 320b shown in fig. 3 (b) and the sampling circuit 320c shown in fig. 3 (c) can flexibly set the driving voltage value by changing the number of turns of the first auxiliary winding T1B and the second auxiliary winding L1A, respectively, and can reduce the driving voltage by reducing the number of turns of the first auxiliary winding T1B and the second auxiliary winding L1A, respectively, when the input voltage is high, thereby avoiding excessive energy loss on the switching tube Q5 and improving the conversion efficiency of the synchronous rectification circuit.
The synchronous rectification driving circuits described in all the embodiments above can be used for synchronous rectification circuits with various topologies, such as a forward secondary side active clamp circuit topology, a forward primary side active clamp circuit topology 400 shown in fig. 4, and a capacitance reset forward circuit topology 500 shown in fig. 5. When the primary side switching tube Q1 is conducted, the dotted terminal of the transformer T1 is positive, and the synchronous rectification circuit is in a rectification stage; when the primary side switching tube Q1 is turned off, the dotted terminal of the transformer T1 is negative, and the synchronous rectification circuit is in a freewheeling stage.
As a specific embodiment of the present application, the synchronous rectification driving circuit in fig. 4 and 5 has the structure shown in fig. 3 (b); in fact, for the synchronous rectification circuit with any topology structure, the synchronous rectification driving circuit can adopt the structure described in any embodiment.
It will be understood by those skilled in the art that all or part of the processes of the methods of the embodiments described above can be implemented by a computer program, which can be stored in a computer-readable storage medium, and can include the processes of the embodiments of the methods described above when the computer program is executed. The storage medium may be a magnetic disk, an optical disk, a Read-only memory (ROM), a Random Access Memory (RAM), or the like.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the application. Thus, the present application is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims (8)
1. A synchronous rectification drive circuit is characterized by being applied to a synchronous rectification circuit; the synchronous rectification circuit comprises a rectification tube and a follow current tube; the synchronous rectification drive circuit comprises:
the sampling circuit is used for acquiring and outputting sampling voltage representing the input voltage of the synchronous rectification circuit;
the driving main circuit comprises a first resistor and a switching tube and is used for controlling the rectifying tube and the follow current tube to be conducted alternately;
the clamping circuit is used for clamping the grid voltage of the switching tube when the rectifying tube is conducted;
the discharge circuit is used for discharging the grid electrode of the rectifying tube when the follow current tube is conducted so as to rapidly turn off the rectifying tube; wherein,
a first output end of the sampling circuit is respectively connected with one end of the first resistor and an input end of the clamping circuit; the second output end of the sampling circuit is connected with the negative output end of the synchronous rectification circuit;
the other end of the first resistor is connected with the drain electrode of the switch tube, and the source electrode of the switch tube is connected with the grid electrode of the rectifier tube; the grid electrode of the switching tube is connected to the output end of the clamping circuit;
the discharge circuit is respectively connected with the grid electrode of the rectifier tube and the drain electrode of the follow current tube;
the clamping circuit comprises a third diode, a voltage stabilizing diode, a second resistor, a third resistor and a capacitor;
the anode of the third diode is used as the input end of the clamping circuit; the cathode of the third diode is connected to one end of the second resistor;
the cathode of the voltage stabilizing diode is used as the output end of the clamping circuit and is connected to the other end of the second resistor in parallel; the anode of the voltage stabilizing diode is connected with the negative output end of the synchronous rectification circuit;
and the third resistor and the capacitor are respectively connected with the voltage stabilizing diode in parallel.
2. The synchronous rectification drive circuit of claim 1, wherein the discharge circuit comprises a first diode; the anode of the first diode is connected with the grid electrode of the rectifier tube, and the cathode of the first diode is connected with the drain electrode of the follow current tube.
3. The synchronous rectification drive circuit as claimed in any one of claims 1 to 2, wherein the synchronous rectification circuit further comprises a transformer having a primary winding and a secondary winding;
the sampling circuit is specifically the secondary winding; and the homonymous end of the secondary winding is used as a first output end of the sampling circuit, and the heteronymous end of the secondary winding is used as a second output end of the sampling circuit.
4. The synchronous rectification drive circuit as claimed in any one of claims 1 to 2, wherein the synchronous rectification circuit further comprises a transformer having a primary winding and a secondary winding;
the sampling circuit is specifically a first auxiliary winding coupled with the primary winding; the homonymous end of the first auxiliary winding is used as a first output end of the sampling circuit, and the synonym end of the first auxiliary winding is used as a second output end of the sampling circuit.
5. The synchronous rectification drive circuit of claim 4, wherein the main drive circuit further comprises a second diode connected in series between the first output terminal of the sampling circuit and the first resistor, an anode of the second diode is connected to the first output terminal of the sampling circuit, and a cathode of the second diode is connected to the first resistor.
6. The synchronous rectification drive circuit as claimed in any one of claims 1 to 2, wherein the synchronous rectification circuit further comprises an output inductor and a transformer having a primary winding and a secondary winding; the homonymous end of the output inductor is connected with the homonymous end of the secondary winding, and the heteronymous end of the output inductor is used as the positive output end of the synchronous rectification circuit;
the sampling circuit is specifically a second auxiliary winding coupled with the output inductor; and the homonymous end of the second auxiliary winding is used as a first output end of the sampling circuit, and the synonym end of the second auxiliary winding is used as a second output end of the sampling circuit.
7. The synchronous rectification drive circuit of claim 6, wherein the main drive circuit further comprises a second diode connected in series between the first output terminal of the sampling circuit and the first resistor, an anode of the second diode is connected to the first output terminal of the sampling circuit, and a cathode of the second diode is connected to the first resistor.
8. The synchronous rectification drive circuit as claimed in any one of claims 1 to 2, wherein the topological structure of the synchronous rectification circuit is a forward primary side active clamp circuit topology, a forward secondary side active clamp circuit topology or a capacitance reset forward circuit topology.
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| CN105846657A (en) * | 2016-05-30 | 2016-08-10 | 西安电子工程研究所 | Synchronous rectification self-driving circuit |
| CN107147277A (en) * | 2017-06-29 | 2017-09-08 | 中国航空工业集团公司雷华电子技术研究所 | Drive Protecting Circuit and DC converter for synchronous rectifier |
| CN111293858B (en) * | 2018-12-07 | 2022-04-29 | 河南嘉晨智能控制股份有限公司 | Self-driven synchronous rectification circuit of forward converter |
| CN111953216B (en) * | 2020-08-25 | 2024-07-19 | 广州金升阳科技有限公司 | Driving circuit of synchronous rectification circuit and driving method thereof |
| CN113241932B (en) * | 2021-04-30 | 2025-03-18 | 北京七星华创微电子有限责任公司 | A new hybrid synchronous rectification drive circuit |
| CN113364304B (en) * | 2021-08-10 | 2022-06-14 | 深圳市力生美半导体股份有限公司 | Synchronous rectification sampling control circuit, method and chip |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5590032A (en) * | 1995-05-25 | 1996-12-31 | Lucent Technologies Inc. | Self-synchronized drive circuit for a synchronous rectifier in a clamped-mode power converter |
| EP1229635A2 (en) * | 2001-01-25 | 2002-08-07 | Texas Instruments Incorporated | Active gate clamp circuit for self driven synchronous rectifiers |
| CN1479439A (en) * | 2002-08-30 | 2004-03-03 | 艾默生网络能源有限公司 | Inserting position driving circuit |
| CN1545196A (en) * | 2003-11-21 | 2004-11-10 | 华南理工大学 | A voltage self-driven synchronous rectification circuit |
| CN101047338A (en) * | 2007-04-29 | 2007-10-03 | 艾默生网络能源有限公司 | Synchronous rectificiation circuit of DC/DC inverter |
-
2013
- 2013-08-05 CN CN201310337230.2A patent/CN103368425B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5590032A (en) * | 1995-05-25 | 1996-12-31 | Lucent Technologies Inc. | Self-synchronized drive circuit for a synchronous rectifier in a clamped-mode power converter |
| EP1229635A2 (en) * | 2001-01-25 | 2002-08-07 | Texas Instruments Incorporated | Active gate clamp circuit for self driven synchronous rectifiers |
| CN1479439A (en) * | 2002-08-30 | 2004-03-03 | 艾默生网络能源有限公司 | Inserting position driving circuit |
| CN1545196A (en) * | 2003-11-21 | 2004-11-10 | 华南理工大学 | A voltage self-driven synchronous rectification circuit |
| CN101047338A (en) * | 2007-04-29 | 2007-10-03 | 艾默生网络能源有限公司 | Synchronous rectificiation circuit of DC/DC inverter |
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|---|---|
| CN103368425A (en) | 2013-10-23 |
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